Andrea Leadsom has refuted accusations that the Government has acted in contempt of Parliament by refusing to publish legal advice on the Brexit deal.
The Commons Leader said ministers had treated MPs "with the greatest of respect" as she argued that Attorney General Geoffrey Cox had gone out of his way to satisfy Parliament's motion calling for the release of the full legal text provided to Cabinet on Theresa May's deal.
MPs will vote on the motion on Tuesday afternoon, which will then allow for the Brexit debate to start. These debates are expected to last for eight hours a day for five days before a vote on the Withdrawal Agreement Mrs May has agreed on December 11.
Mr Cox, who is the Government's chief legal adviser, published an overview of his legal advice on Monday but opposition parties said that, by limiting the information released, ministers had ignored the demands of MPs.
Shadow Brexit secretary Sir Keir Starmer, moving a motion of contempt, told MPs the Government had been "wilfully refusing to comply" with the binding Commons order.
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Sir Keir, addressing the Government amendment which asks a committee to examine claims that ministers are in contempt of Parliament over the issue, said: "There is nothing to refer - a binding order was made and the Government is refusing to comply with it.
"The reality is, yet again, by its amendment, the Government is simply playing for time in the hope that this ends up in the long grass until the crucial vote is long gone."
Mrs Leadsom, responding to the contempt motion, warned MPs they must "exercise caution in this matter".
She said: "The use of this motion has happened very rarely in the history of Parliament and I don't think any member of this House can be in any doubt that the information that the Attorney General provided yesterday was a very frank assessment of the legal position.
"The questions posed by members on all sides addressed the key issues we must all consider on the legal effect of the Withdrawal Agreement."
She added: "No honourable member could say in all honesty that the Attorney General has done anything other than treat this House with the greatest of respect, there can be no question that he or the Government has acted in a manner which is contemptuous of this House."
Liberal Democrat Brexit spokesman Tom Brake said: “MPs expect the publication of the full legal Brexit advice before the debates on the withdrawal deal begin.
Nadine Dorries speaking during the debate
“The Government must not be allowed to use this chaotic situation to take focus away from the mess they are making of Brexit.”
The cross-party motion tabled by Labour, the SNP, Lib Dems, DUP, Plaid Cymru and Green Party states that the House of Commons finds ministers in contempt for failing to comply with the resolution passed by MPs in November demanding the legal advice and “orders its immediate publication”.
Conservative MP Nadine Dorries told the House of Commons that it would be a "disgrace" if the Government was found in contempt of Parliament.
Attorney General Cox was repeatedly challenged about the issue in the Commons on Monday but insisted it was in the public interest for the advice he gave to ministers to remain confidential.
“The House has at its disposal the means by which to enforce its will,” he acknowledged.
“It can bring a motion of contempt and seek to have that motion passed and seek to impose through the committee, or whichever way it is appropriately done, to impose a sanction. I fully accept that.
“I don’t set myself up contrary to the House, I simply say that I cannot compromise the public interest.”
Jacob Rees-Mogg enjoys a lighthearted moment during the debate
Conservative Jacob Rees-Mogg told the Commons he would support the Government, although he did not agree with the dismissal of "ancient procedures" like the humble address being used to hold it to account.
He said: "I think it's right that a committee looks at this issue in broad terms because it may be right that the House wishes to take a self-denying ordinance on the extent of humble addresses.
"It may be right we would like to say specifically they would be deemed disorderly and therefore not brought forward if they related to matters concerning the security services."
DUP Westminster Leader Nigel Dodds criticised the Government for ignoring the motion passed by the House and refusing to release the full Brexit legal advice.
He said it was not up to Mr Cox to decide whether it was "in the national interest" to publish it, saying it was "the duty of Parliament".
"Despite all of the candour and all of what was said yesterday; the coming to this house and making a two-and-a-half-hour oral statement and taking all of the questions and proving the reasoned position paper, does not actually fulfil the motion that was passed by this House," he added.
His DUP colleague Sammy Wilson intervened to say: "If the Government, and the Prime Minister, is going round the country trying to convince the populace that this is a good deal, this secret approach only confirms in people's minds that there's something to hide, and if anything the Government is scoring an own goal by refusing to provide this advice."
Mr Dodds agreed and accused members of the Cabinet of releasing some of the advice to the media, adding: "If the press are entitled, then the members of this House are entitled to have this advice."
The issue risks overshadowing Mrs May’s effort to win over MPs ahead of the showdown in a week’s time.
The Prime Minister faces widespread opposition from MPs across the Commons – including both the Leave and Remain wings of her own party – ahead of the vote.
Over the coming days she will deploy senior Cabinet ministers to make the case, with Chancellor Philip Hammond, Foreign Secretary Jeremy Hunt and Home Secretary Sajid Javid expected to appear at the despatch box.
Mrs May will say that to respect the 2016 referendum result would require “a Brexit that takes back control of our borders, laws and money” and “a Brexit that sets ourselves on course for a better future outside the EU, as a globally trading nation, in charge of our own destiny and seizing the opportunities of trade with some of the fastest-growing and most dynamic economies across the world”.
The Prime Minister will assert that her Brexit deal, thrashed out over months of negotiations in Brussels, delivers on her commitments to end free movement and the jurisdiction of the European Court of Justice.
It will also ultimately result in “a new free trade area with no tariffs, fees, quantitative restrictions or rules of origin checks – an unprecedented economic relationship that no other major economy has”.
She will tell MPs: “The British people want us to get on with a deal that honours the referendum and allows us to come together again as a country, whichever way we voted.
“This is the deal that delivers for the British people.”
Critics of the deal seized on Mr Cox’s comments on the backstop measure aimed at avoiding a hard border with Ireland if no alternatives are found.
The backstop is highly controversial, with Brexiteer MPs claiming it traps the UK into obeying rules set by Brussels without a say over them.
Mr Cox acknowledged neither the UK nor the EU had the right to terminate the backstop agreement unilaterally if it came into effect, even if talks on a future trade deal to replace it broke down.
“I make no bones about it – I would have preferred to have seen a unilateral right of termination in this backstop,” he told MPs.
But he added: “I’m prepared to lend my support to this agreement because I do not believe that we’re likely to be entrapped in it permanently.”